package 齐祥进;

import java.util.LinkedHashSet;
import java.util.Scanner;

public class data3 {
    public static void main(String[] args) {
        //录入一个字符串
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();

        //把字符串存放在字符数组
        char[] as = str.toCharArray();

        //创建集合对象,把字符存放到set集合中
        LinkedHashSet<Character> list = new LinkedHashSet<>();
        for (int i = 0; i < as.length; i++) {
            list.add(as[i]);
        }

        for (Character character : list) {
            System.out.print(character);
        }
    }
}
